Methods and devices for minimally-invasive delivery of radiation to the eye

ABSTRACT

Methods and devices for minimally-invasive delivery of radiation to the eye (such as the posterior portion of the eye) including cannula systems with multiple treatment positions and/or multiple channels in the distal tip of the cannula systems. The channels can accommodate emanating sources and exposing a target at various treatment positions. The emanating sources may be annulus-shaped.

CROSS REFERENCE

This application is a divisional of U.S. patent application Ser. No.14/486,401, filed Sep. 15, 2014, which is a non-provisional of andclaims priority to U.S. Provisional Patent Application No. 61/877,765,filed Sep. 13, 2013, the specification(s) of which is/are incorporatedherein in their entirety by reference.

U.S. patent application Ser. No. 14/486,401 also claims priority to U.S.patent application Ser. No. 13/872,941, filed Apr. 29, 2013, which is adivision of U.S. patent application Ser. No. 12/350,079, filed Jan. 7,2009, which is a non-provisional of U.S. Provisional Application No.61/010,322, filed Jan. 7, 2008, U.S. Provisional Application No.61/033,238, filed Mar. 3, 2008, U.S. Provisional Application No.61/035,371, filed Mar. 10, 2008, and U.S. Provisional Application No.61/047,693, filed Apr. 24, 2008, the specification(s) of which is/areincorporated herein in their entirety by reference.

U.S. patent application Ser. No. 14/486,401 also claims priority to U.S.patent application Ser. No. 13/953,528, filed Jul. 29, 2013, which is anon-provisional of U.S. Provisional Application No. 61/676,783, filedJul. 27, 2012, the specification(s) of which is/are incorporated hereinin their entirety by reference.

U.S. patent application Ser. No. 14/486,401 also claims priority to U.S.patent application Ser. No. 14/011,516, filed Aug. 27, 2013, whichclaims priority to U.S. patent application Ser. No. 13/742,823, filedJan. 16, 2013, which is a continuation of U.S. patent application Ser.No. 12/497,644, filed Jul. 3, 2009, which is a continuation-in-part ofU.S. patent application Ser. No. 12/350,079, filed Jan. 7, 2009, whichis a non-provisional of U.S. Provisional Application No. 61/010,322,filed Jan. 7, 2008, U.S. Provisional Application No. 61/033,238, filedMar. 3, 2008, U.S. Provisional Application No. 61/035,371, filed Mar.10, 2008, and U.S. Provisional Application No. 61/047,693, filed Apr.24, 2008, the specification(s) of which is/are incorporated herein intheir entirety by reference. Application Ser. No. 14/011,516 also claimspriority to U.S. patent application Ser. No. 13/111,780, filed May 19,2011, which is a non-provisional of U.S. Provisional Application No.61/347,226, filed May 21, 2010; and a continuation-in-part of U.S.patent application Ser. No. 12/497,644, filed Jul. 3, 2009, which is acontinuation-in-part of U.S. patent application Ser. No. 12/350,079,filed Jan. 7, 2009, which is a non-provisional of U.S. ProvisionalApplication No. 61/010,322, filed Jan. 7, 2008, U.S. ProvisionalApplication No. 61/033,238, filed Mar. 3, 2008, U.S. ProvisionalApplication No. 61/035,371, filed Mar. 10, 2008, and U.S. ProvisionalApplication No. 61/047,693, filed Apr. 24, 2008, the specification(s) ofwhich is/are incorporated herein in their entirety by reference.Application Ser. No. 14/011,516 also claims priority to U.S. patentapplication Ser. No. 12/917,044, filed Nov. 1, 2010, which is anon-provisional of U.S. Provisional Application Ser. No. 61/257,232,filed Nov. 2, 2009 and U.S. Provisional Application No. 61/376,115,filed Aug. 23, 2010, the specification(s) of which is/are incorporatedherein in their entirety by reference. Application Ser. No. 14/011,516also claims priority to U.S. patent application Ser. No. 13/111,765,filed May 19, 2011, which is a non-provisional of U.S. ProvisionalApplication No. 61/347,233, filed May 21, 2010, the specification(s) ofwhich is/are incorporated herein in their entirety by reference.Application Ser. No. 14/011,516 also claims priority to U.S. patentapplication Ser. No. 13/953,528, filed Jul. 29, 2013, which is anon-provisional of U.S. Provisional Application No. 61/676,783, filedJul. 27, 2012, the specification(s) of which is/are incorporated hereinin their entirety by reference.

FIELD OF THE INVENTION

The present invention relates to methods and devices for introducingradiation to the eye, e.g., the posterior portion of the eye, fortreating and/or managing eye conditions including but not limited tomacular degeneration.

BACKGROUND OF THE INVENTION

The present invention features methods and devices forminimally-invasive delivery of radiation to the eye, e.g., the posteriorportion of the eye. For example, the present invention features cannulasystems and afterloading systems (e.g., remote afterloading systems) forintroducing emanating sources (e.g., active material, radionuclidebrachytherapy sources) to the cannula systems for irradiating targets(e.g., targets of the eye). The emanating source may be, for example,introduced into the cannula system via an afterloading system followingcannula system insertion and positioning.

Presently, workers in the field of radiation therapy believe that abarrel-shaped or disk-shaped radiation projection at the surface of theradiation source is the proper radiation profile for treatingneovascular lesion of wet AMD. We have surprisingly discovered thatradiation flux with an attenuation zone, e.g., a centrally disposedattenuation zone, provides for more effective treatment of neovascularlesion of wet AMD from the posterior episcleral surface.

Any feature or combination of features described herein are includedwithin the scope of the present invention provided that the featuresincluded in any such combination are not mutually inconsistent as willbe apparent from the context, this specification, and the knowledge ofone of ordinary skill in the art. Additional advantages and aspects ofthe present invention are apparent in the following detailed descriptionand claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an in-use view of a cannula system of the presentinvention.

FIG. 2 shows a schematic view of an afterloading system of the presentinvention. Afterloading systems are well known to one of ordinary skillin the art. The present invention is not limited to the afterloadingsystems described herein.

FIG. 3A shows the advancing means and emanating source within the guidetube.

FIG. 3B shows the guide tube connecting to the cannula system.

FIG. 4A shows a detailed view of the distal portion of a cannula systemcomprising a single channel through which an emanating source cantravel. The cannula system comprises a plurality of treatment positionswithin the channel (e.g., treatment position 1, treatment position 2,treatment position n, treatment position n+1, etc.).

FIG. 4B shows a detailed view of the distal portion of a cannula systemcomprising more than one channel (e.g., 2 channels) through which anemanating source can travel, wherein the channels each comprise morethan one treatment position (e.g., treatment position 1, treatmentposition 2) for the emanating source.

FIG. 5 shows the insertion of a fixed shape cannula according to thepresent invention. The tip of the cannula system is positioned at theback of the eye. Part (220) refers to the visual axis of the user; Part(230) refers to the Tenon's capsule; Part (235) refers to the sclera;Part (500) refers to an orifice; Part (510) refers to a window. Thepresent invention is not limited to the configuration and parts of thecannula shown in FIG. 5.

FIG. 6A shows a side view of a light source assembly.

FIG. 6B shows a perspective view of a light source assembly.

FIG. 60 shows a bottom view of the light source assembly of FIG. 6B (asviewed from the bottom (or sclera-contacting surface) of the tip of thedistal portion of the cannula system). The emanating source may bediscrete units or a continuous ring (or partial ring, not shown). Theemanating sources are not limited to these configurations.

FIG. 7A shows the annulus-shaped emanating source at the tip of acannula system.

FIG. 7B shows an emanating source with an annulus-like radiation profiledisposed in the tip of the cannula system (100).

FIG. 8 shows an annulus-shaped emanating source and an emanating sourcethat has an annulus-shaped radiation emission shape because of theradiation shaper positioned between the target and the emanating source.

FIG. 9A shows examples of emanating sources (or radiation emissionshapes).

FIG. 9B shows additional examples of emanating sources (or radiationemission shapes) with attenuation zones.

FIG. 10 shows examples of emanating source shapes (or radiation emissionshapes).

FIG. 11 shows side cross sectional views of two examples of emanatingsource configurations, one with an indentation and one with a hole.

FIG. 12 shows radiation flux for two annulus emanating sources: (a) anannulus-shaped emanating source and a disc-shaped emanating sourcepaired with a radiation shaper. The resulting radiation emission shapeis that of an annulus configuration.

DESCRIPTION OF PREFERRED EMBODIMENTS

Following is a list of elements corresponding to a particular elementreferred to herein:

100 cannula system

110 distal portion of cannula system

112 tip/distal end of distal portion of cannula system

113 center

114 light aperture in tip of distal portion of cannula system

116 light source plug compartment

118 treatment position

120 proximal portion of cannula system

130 inflection point of cannula system

140 handle

150 connector (optional)

160 channel

401 emanating source

401 a annulus-shaped emanating source

401 b disc-shaped emanating source

402 jacket

404 radiation shaper

406 radiation emission shape

407 annulus-shaped radiation emission shape

410 attenuation zone

412 outer edge of attenuation zone

414 hole

416 indentation

450 radiation flux

600 light source assembly

610 light source emitter component

612 light pipe (e.g., fiber optic cable or other light guide)

613 prism

614 light source plug

616 tip of light source plug

617 locking mechanism

618 groove

700 afterloading system

710 vault

720 guide tube

722 advancing means (e.g., guide wire)

730 source-drive mechanism

732 motor

740 computer (e.g., microprocessor)

744 control console

Referring now to FIG. 1-12, the present invention features methods anddevices for minimally-invasive delivery of radiation to the eye, e.g.,the posterior portion of the eye. For example, the present inventionfeatures afterloading systems (700) (e.g., remote afterloading systems)for introducing an emanating source (401) to a cannula system (100). Thecannula system (100) may be adapted for insertion into a potential spacebetween the sclera and the Tenon's capsule of the eye of a patient.

The present methods and devices may be effective for treating and/ormanaging a condition (e.g., an eye condition). For example, the presentmethods and devices may be used to treat and/or manage wet (neovascular)age-related macular degeneration. The present methods are not limited totreating and/or managing wet (neovascular) age-related maculardegeneration. For example, the present methods may also be used to applysuperficial radiation to benign or malignant ocular growths (e.g.,choroidal hemangioma, choroidal melanoma, retinoblastoma) and or totreat and/or manage conditions including macular degeneration, abnormalcell proliferation, choroidal neovascularization, retinopathy (e.g.,diabetic retinopathy, vitreoretinopathy), macular edema, and tumors.

In some embodiments, the present invention features an emanating sourcesystem, the emanating source system comprising an emanating source (401)whereby the radiation emission shape (406) is in the shape of an annulusor partial annulus. In some embodiments, the emanating source (401) isin the shape of an annulus or a partial annulus. In some embodiments,the emanating source (401) comprises a plurality of discrete seeds thathave a cumulative radiation emission shape (406) of an annulus orpartial annulus. In some embodiments, the emanating source (401)comprises any arrangement of sources that yield a radiation emissionshape (406) in the shape of an annulus or partial annulus. In someembodiments, the emanating source (401) comprises a radiation shaper(404); the radiation shaper (404) shapes the radiation emitted from theemanating source (401) into a radiation emission shape (406) in theshape of an annulus or partial annulus. In some embodiments, theemanating source (401) unit is housed in a jacket (402). In someembodiments, the emanating source (401) unit is attached to a cannula, acannula system (100), a rod, or a stick.

In some embodiments, the present invention features a method ofirradiating a target of an eye in a patient, said method comprisingexposing a target of an eye with an emanating source (401) that has anradiation emission shape (406) of an annulus. In some embodiments, thetarget comprises a neovascular lesion of wet AMD. In some embodiments,the emanating source (401) is adjacent to the retrobulbar episcleralsurface.

In some embodiments, the present invention features a method ofirradiating a target of an eye in a patient, said method comprisinginserting a cannula system into a potential space between a sclera and aTenon's capsule of the eye of the patient; placing a distal portion(110) of the cannula system (100) on or near the sclera and positioninga treatment position (118) of a tip (112) of the distal portion (110) ofthe cannula system (100) near the target; advancing an emanating source(401) through the cannula system (100) to the treatment position (118)in the distal portion (110) of the cannula system (100), wherein theradiation emission shape (406) of the emanating source (401) creates aradiation emission shape (406) of an annulus; exposing the target to theemanating source (401); retracting the emanating source (401); andremoving the cannula system (100). In some embodiments, the emanatingsource (401) comprises a single unit or a plurality of discrete unitsthat are positioned either simultaneously or by sequential positioning.In some embodiments, the cannula system comprises a cannula system(100).

In some embodiments, the present invention features a method ofirradiating a target of an eye in a patient, said method comprisingadvancing an emanating source (401) through a cannula system (100) to atreatment position (118) in a distal portion (110) of a cannula system(100); inserting the cannula system (100) into a potential space betweena sclera and a Tenon's capsule of the eye of the patient; placing adistal portion (110) of the cannula system (100) on or near the scleraand positioning the treatment position (118) of the cannula system (100)near the target; exposing the target to the emanating source (401); andremoving the cannula system (100). In some embodiments, the emanatingsource (401) comprises a single unit or a plurality of discrete unitsthat are positioned either simultaneously or by sequential positioning.In some embodiments, the cannula system comprises a cannula system(100).

In some embodiments, the present invention features a brachytherapysystem comprising a cannula system (100) for insertion into a potentialspace between a sclera and a Tenon's capsule of an eye of a patient. Insome embodiments, the cannula system (100) comprises a distal portion(110) with a tip (112), a channel (160) extends through the cannulasystem (100) to the tip (112), the channel (160) comprises at least onetreatment position (118) in the tip (112) for an emanating source (401).

In some embodiments, the cannula system (100) comprises two channels(160). In some embodiments, the cannula system (100) comprises threechannels (160). In some embodiments, the cannula system (100) comprisesfour channels (160). In some embodiments, the cannula system (100)comprises more than four channels (160).

In some embodiments, the channel (160) comprises two treatment positions(118). In some embodiments, the channel (160) comprises three treatmentpositions (118). In some embodiments, the channel (160) comprises fourtreatment positions (118). In some embodiments, the channel (160)comprises five treatment positions (118). In some embodiments, thechannel (160) comprises six treatment positions (118). In someembodiments, the channel (160) comprises more than six treatmentpositions (118).

In some embodiments, the emanating source (401) is directed through oneor more channels (160) to one or more treatment positions (118) that insummation deliver a dose to the target approximating that emanating froman annulus. In some embodiments, the tip (112) of the cannula system(100) is disk-shaped. In some embodiments, the emanating source (401) ishorseshoe shaped. In some embodiments, the emanating source (401) is anannulus or a partial annulus. In some embodiments, the emanating source(401) is linear. In some embodiments, the emanating source (401)comprises one or more discrete seeds.

In some embodiments, the discrete seeds are arranged in an annulus orpartial annulus configuration. In some embodiments, the emanating source(401) comprises a continuous ring or a portion of a ring. In someembodiments, the brachytherapy system further comprises a light sourceassembly (600).

In some embodiments, the light source assembly (600) comprises a fiberoptic cable or light pipe (612) operatively connected to an externallight source. a light source plug (614) is disposed on an end of thefiber optic cable or light pipe (612), a light source emitter component(610) is incorporated into the light source plug (614), the light sourceplug (610) and light source emitter component (610) are adapted toengage a light source plug compartment (116) disposed in the tip (112)of the distal portion (110) of the cannula system (100). In someembodiments, the light source plug (614) and light source emittercomponent (610) engage a light aperture (114) disposed on a bottomsurface of the tip (112) of the cannula system (100). In someembodiments, a prism is disposed at the end of the fiber optic cable orlight pipe (612). In some embodiments, the light source plug (614) issecured in the light source plug compartment (116) via a lockingmechanism. In some embodiments, a groove (618) is disposed in thecannula system (100) adapted to engage the fiber optic cable or lightpipe (612).

In some embodiments, the brachytherapy system further comprises anafterloading system (700) for delivering the emanating sources (401)(400) to the treatment position(s) (118). In some embodiments, theafterloading system (700) comprises a guide tube (720) for each channel(160) in the cannula system (100). In some embodiments, the afterloadingsystem (700) comprises: a vault (710) for storage of an emanating source(401), wherein the emanating source (401) is attached to an advancingmeans (722); a guide tube (720) extending from the vault (710), theguide tube (720) is removably attachable to the cannula system (100);and a source-drive mechanism (730) operatively connected to theadvancing means (722), wherein the source-drive mechanism (730) advancesthe emanating source (401) through the guide tube (720) to the treatmentposition (118) in the cannula system (100). In some embodiments, theemanating source (401) provides a dose rate of between about 1 to 10Gy/min to a target.

In some embodiments, the cannula system (100) comprises a proximalportion (120) connected to the distal portion (110) by an inflectionpoint (130), the distal portion (110) has a radius of curvature betweenabout 9 to 15 mm and an arc length between about 25 to 35 mm and theproximal portion (120) has a radius of curvature between about an innercross-sectional radius of the cannula system (100) and about 1 meter.

In some embodiments, the present invention features a method ofirradiating a target of an eye in a patient, said method comprisinginserting a cannula system (100) into a potential space between a scleraand a Tenon's capsule of the eye of the patient; placing a distalportion (110) of the cannula system (100) on or near the sclera andpositioning a treatment position (118) of a tip (112) of the distalportion (110) of the cannula system (100) near the target; advancing anemanating source (401) through the cannula system (100) to the treatmentposition (118) in the distal portion (110) of the cannula system (100);exposing the target to the emanating source (401); retracting theemanating source (401); and removing the cannula system (100).

In some embodiments, the emanating source (401) travels to eachtreatment position (118) sequentially. In some embodiments, theemanating source (401) travels to selected treatment positions (118)sequentially. In some embodiments, the emanating source (401) travels toeach treatment positions (118) in a selected order. In some embodiments,the emanating source (401) travels to selected treatment positions (118)in a selected order. In some embodiments, the cannula system (100) isoperatively connected to an afterloading system (700). In someembodiments, the afterloading system (700) is operatively connected tothe cannula system (100) after the cannula system (100) is positioned inbetween the Tenon's capsule and sclera. In some embodiments, theafterloading system (700) is operatively connected to the cannula system(100) before the cannula system (100) is positioned in between theTenon's capsule and sclera. In some embodiments, both (a) theafterloading system (700) is operatively connected to the cannula system(100) and (b) the emanating source (401) is advanced before the cannulasystem (100) is positioned in between the Tenon's capsule and sclera.

Cannula System

As shown in FIG. 1, the cannula system (100) comprises a distal portion(110) and a proximal portion (120) connected by an inflection point(130). The distal portion (110) is generally for placement around aportion of the globe of the eye. In some embodiments, the distal portion(110) has a radius of curvature between about 9 to 15 mm and an arclength between about 25 to 35 mm. In some embodiments, the proximalportion (120) has a radius of curvature between about an innercross-sectional radius of the cannula system (100) and about 1 meter.The cannula system (100), or a portion thereof, may be flexible,fixed-shape, or a combination thereof. The cannula system (100) is notlimited to the aforementioned dimensions and configurations.

The cannula system (100) may be operatively connected to an afterloadingsystem (700) having an emanating source (401). The afterloading system(700) can deliver the emanating source (401) to the cannula system (100)(e.g., to a treatment position (118) of the cannula system (100), to atleast one treatment position, to one or more treatment positions, etc.).For example, the afterloading system (700) can direct the emanatingsource (401) to a position within the cannula system (100) (e.g., atreatment position (118), at least one treatment position, one or moretreatment positions, etc.) such that the emanating source (401) is overa target. The emanating source (401) can then irradiate the target for alength of time desired. The afterloading system (700) may also functionto remove the emanating source (401) from the position within thecannula system (e.g., the treatment position(s) (118)) and from thecannula system (100) altogether. For example, the afterloading system(700) may retract the emanating source (401) to its starting positionoutside of the cannula system (100).

The cannula system (100) may comprise one or more treatment positions(118) and/or channels (160) (as described below). In some embodiments,an afterloading system (700) may function to deliver one or moreemanating sources (401) to one or more treatment positions (118) in oneor more channels (160) of the cannula system (100).

In some embodiments, the cannula system (100) is inserted, e.g., intothe potential space between the sclera and the Tenon's capsule, and ispositioned appropriately prior to attachment of the afterloading system(700). For example, the distal portion (110) of the cannula system isplaced on or near the sclera and the treatment position(s) (118) of thecannula system (100) (e.g., in the distal portion (110)) or treatmentposition(s), is positioned near the target. Following placement andpositioning of the cannula system, the afterloading system (700) may beconnected to the cannula system. In some embodiments, the cannula system(100) and the afterloading system (700) are connected prior to insertionof the cannula system (100), e.g., into the potential space between thesclera and the Tenon's capsule. In some embodiments, the cannula system(100) and the afterloading system (700) are connected prior to insertionof the cannula system (100), e.g., into the potential space between thesclera and the Tenon's capsule, and the emanating source (401) advancedto the treatment position prior to the cannula system being introducedto the sub-tenon's space.

In some embodiments, the cannula system (100) is connected to a handleand/or shielding system (e.g., radiation shielding PIG). For example,the cannula system (100) in FIG. 5 is attached to a handle (140).

Afterloading System

The afterloading system (700) may allow for accurate placement of theemanating source (401), e.g., at the treatment position(s) (118) withinthe cannula system (100). Afterloading systems (700) are well known toone of ordinary skill in the art and any appropriate afterloading system(700) may be utilized. For example, in some embodiments, theafterloading system (700) comprises a vault (710) for temporary housingof the emanating source (401). The emanating source (401) may beattached to an advancing means (722) (e.g., a guide wire). In someembodiments, the emanating source (401) may be incorporated into theadvancing mean (722) (e.g., guide wire). The advancing means (722)(e.g., guide wire) may be constructed from any appropriate materialincluding but not limited to nitinol and stainless steel. A guide tube(720) extends from the vault (710) and is connected to the cannulasystem (100). In some embodiments, the guide tube (720) connects, e.g.,removably connects, to the cannula system (100) via a connector (150).In some embodiments, the connector (150) is disposed on the cannulasystem (100), e.g., on the proximal portion (120) of the cannula system(100). The advancing means (722) directs the emanating source (401)through the guide tube (720), e.g., the advancing means (722) may bedisposed in at least a portion of the guide tube (720).

The afterloading system (700) comprises a source-drive mechanism (730)operatively connected to the advancing means (722) (e.g., guide wire).The source-drive mechanism (730) functions to advance the advancingmeans (722) (e.g., guide wire) and emanating source (401) through theguide tube (720) to the treatment position(s) (118) in the cannulasystem (100). In some embodiments, the source-drive mechanism (730)comprises a motor (732). In some embodiments, the motor (732) comprisesdrive rollers or belts.

In some embodiments, the afterloading system (700) comprises a computer(740) (e.g., a microprocessor) or other controller (e.g., an analog or amechanical control system). The motor (732) and/or source-drivemechanism (730) may be operatively connected to the computer (740) orother controller. In some embodiments, the computer (740) or othercontroller is operatively connected to a control console (744). Thecontrol console (744) allows for manipulation of the computer (740) orother controller. For example, the control console (744) may allow forprogramming of the afterloading system (700), e.g., dwell time of theemanating source (401) in the treatment position(s) (118), speed ofdelivery of the emanating source (401), etc. In some embodiments, theafterloading system (700) moves the emanating source (401) from thevault (710) to the treatment position(s) (118) at a rate of betweenabout 0.01 m/s (1 cm/s) to about 4 m/s. In some embodiments, theafterloading system (700) moves the emanating source (401) from thevault (710) to the treatment position(s) (118) at a rate of about 2 m/s.

The afterloading system (700) may measure various parameters of thetreatment. For example, in some embodiments, the afterloading system(700) measures dwell time of the emanating source (401) in the treatmentposition(s) (118).

In some embodiments, the guide tube (720) is constructed from a materialthat provides some shielding from the radiation emitted from theemanating source (401) as it travels through the guide tube (720)

In some embodiments, the afterloading system (700) further comprises aselector, for example for treatments that require multiple applicatorsor cannula systems (100). The selector may provide multiple channels,e.g., between 1 to 10 channels, between 2 to 10 channels, between 2 to20 channels, between 16 to 24 channels, between 18 to 24 channels, morethan 24 channels, etc. The selector may facilitate the movement (e.g.,entry, transfer) of the emanating source (401) through multipleapplicators (e.g., cannula systems (100)), if necessary.

Emanating Source

The methods and devices of the present invention may feature anyappropriate emanating source (401). In some embodiments, the emanatingsource (401) is a high-dose-rate (HDR) source. In some embodiments, theemanating source (401) is a low-dose-rate (LDR) source. In someembodiments, the emanating source (401) is a pulsed-dose-rate (PDR)source. In some embodiments, the emanating source (401), e.g., HDRsource, delivers a dose rate greater than 100 cGy per minute for alength of time. However the present invention is not limited to a HDRsource that delivers a dose rate greater than 100 cGy per minute. Insome embodiments, the emanating source (401) provides a dose rate ofbetween about 2 to 10 Gy/min to the target. In some embodiments, theemanating source (401) provides a dose rate of between about 1 to 10Gy/min to the target. In some embodiments, the emanating source (401)provides a dose rate of between about 2 to 6 Gy/min to the target. Insome embodiments, the emanating source (401) provides a dose rate ofabout 4.4 Gy/min to the target. In some embodiments, a LDR sourceprovides a dose rate of less than about 2 Gy/hour. In some embodiments,a medium-dose-rate (MDR) source provides a dose rate of between about 2to 12 Gy/hour. In some embodiments, a HDR source provides a dose rate ofgreater than about 12 Gy/hour.

In some embodiments, the emanating source (401) provides a dose rate ofgreater than about 10 Gy/min. In some embodiments, the emanating source(401) provides a dose rate of greater than about 11 Gy/min to thetarget. In some embodiments, the emanating source (401) provides a doserate of greater than about 12 Gy/min to the target. In some embodiments,the emanating source (401) provides a dose rate of greater than about 13Gy/min to the target. In some embodiments, the emanating source (401)provides a dose rate of greater than about 14 Gy/min to the target. Insome embodiments, the emanating source (401) provides a dose rate ofgreater than about 15 Gy/min to the target. In some embodiments, theemanating source (401) provides a dose rate between about 10 to 15Gy/min. In some embodiments, the emanating source (401) provides a doserate between about 15 to 20 Gy/min. In some embodiments, the emanatingsource (401) provides a dose rate between about 20 to 30 Gy/min. In someembodiments, the emanating source (401) provides a dose rate betweenabout 30 to 40 Gy/min. In some embodiments, the emanating source (401)provides a dose rate between about 40 to 50 Gy/min. In some embodiments,the emanating source (401) provides a dose rate between about 50 to 60Gy/min. In some embodiments, the emanating source (401) provides a doserate between about 60 to 70 Gy/min. In some embodiments, the emanatingsource (401) provides a dose rate between about 70 to 80 Gy/min. In someembodiments, the emanating source (401) provides a dose rate betweenabout 80 to 90 Gy/min. In some embodiments, the emanating source (401)provides a dose rate between about 90 to 100 Gy/min. In someembodiments, the emanating source (401) provides a dose rate of greaterthan 100 Gy/min.

In some embodiments, the emanating source (401) provides a dose ratebetween about 15 to 20 Gy/min to the target. In some embodiments, theemanating source (401) provides a dose rate between about 20 to 25Gy/min to the target. In some embodiments, the emanating source (401)provides a dose rate between about 25 to 30 Gy/min to the target. Insome embodiments, the emanating source (401) provides a dose ratebetween about 30 to 35 Gy/min to the target. In some embodiments, theemanating source (401) provides a dose rate between about 35 to 40Gy/min to the target. In some embodiments, the emanating source (401)provides a dose rate between about 40 to 50 Gy/min to the target. Insome embodiments, the emanating source (401) provides a dose ratebetween about 50 to 60 Gy/min to the target. In some embodiments, theemanating source (401) provides a dose rate between about 60 to 70Gy/min to the target. In some embodiments, the emanating source (401)provides a dose rate between about 70 to 80 Gy/min to the target. Insome embodiments, the emanating source (401) provides a dose ratebetween about 80 to 90 Gy/min to the target. In some embodiments, theemanating source (401) provides a dose rate between about 90 to 100Gy/min to the target. In some embodiments, the emanating source (401)provides a dose rate greater than about 100 Gy/min to the target.

Multi-Channel-Multi-Treatment Position Cannula System

The cannula system (100) may comprise multiple channels (160) throughwhich an emanating source (401) can travel to the tip/distal end (112)of the distal portion (110) of the cannula system (100) and/or multipletreatment positions (118) for the emanating sources (401) within the tip(112). For example, FIG. 4A shows a cannula system (100) comprising asingle channel (160) through which an emanating source (401) can travelthrough and within the tip (112) of the cannula system (100). Thecannula system (100) comprises a plurality of treatment positions (118)within the channel (160) (e.g., treatment positions positioned in thetip (112) of the cannula system (100)): treatment position 1, treatmentposition 2, treatment position n, and treatment position n+1.

As shown in FIG. 5B of the parent provisional application, a cannulasystem (100) comprises a plurality of channels (160) (e.g., channel 1,channel 2, channel n, channel n+1) through which an emanating source(401) can travel. The cannula system (100) comprises a plurality oftreatment positions (118) (in FIG. 5B each channel (160) has a singletreatment position (118), however in some embodiments each channel (160)may have multiple treatment positions (118)), wherein an emanatingsource (401) in channel 1 is directed to treatment position 1, anemanating source (401) in channel 2 is directed to treatment position 2,an emanating source (401) in channel n is directed to treatment positionn, and an emanating source (401) in channel n+1 is directed to treatmentposition n+1.

FIG. 4B shows an example of a cannula system comprising more than onechannel (e.g., 2 channels) through which an emanating source (401) cantravel, wherein the channels each comprise more than one treatmentposition (e.g., treatment position 1, treatment position 2) for theemanating source (401). The system of the present invention is notlimited to the number of treatment positions, channels, or configurationor arrangements shown herein.

The present invention is not limited to the number of treatmentpositions, channels, or configuration or arrangements of such treatmentpositions and channels shown herein. For example, in some embodiments,the system (100) comprises one treatment position, two treatmentpositions, three treatment positions, four treatment positions, fivetreatment positions, six treatment positions, seven treatment positions,eight treatment positions, nine treatment positions. 10 treatmentpositions, 11 treatment positions, 12 treatment positions, 13 treatmentpositions, 14 treatment positions, 15 treatment positions, 16 treatmentpositions, 17 treatment positions, 18 treatment positions, 19 treatmentpositions, 20 treatment positions, or more than 20 treatment positions.In some embodiments, the system (100) comprises one channel, twochannels, three channels, four channels, five channels, six channels,seven channels, eight channels, nine channels, 10 channels, or more than10 channels. The tip (112) of the distal portion (110) of the cannulasystem (100) is not limited to the shapes (e.g., rounded, circular)described and shown herein.

The emanating sources (401) occupy the treatment position(s) for acertain length of time, or dwell time. The dwell time at the varioustreatment positions may be the same or different.

In some embodiments, the emanating source (401) travels to eachtreatment position (118) in its respective channel (160). In someembodiments, the emanating source (401) travels to selected treatmentpositions (118) in its respective channel (160). In some embodiments,the emanating source (401) travels to each treatment position (or eachselected treatment position (118)) sequentially (e.g., treatmentposition 1, then treatment position 2, then treatment position 3, etc.,or treatment position 5, then treatment position 4, then treatmentposition 3, etc.) or in a selected order (e.g., treatment position 1,then treatment position 5, then treatment position 3, etc.).

Without wishing to limit the present invention to any theory ormechanism, it is believed that the summation of the treatment positions,each with a dwell time (same amount of time or different amounts oftime) may add up in an overlapping fashion to achieve a more uniformdose delivered; this dose delivered may be similar to that of an annulusseed or a ring of seeds.

For example, in reference to figures from provisional application61/877,765, FIG. 6C shows the relative dose distribution for a systemwherein an emanating source (401) (e.g., Sr 90) occupies six treatmentpositions (arranged radially on a 4 mm diameter circle thus spaced adistance of about 2 mm from a center point (113)) in a plane 2 mm awayfrom the target plane (the treatment positions are in a circle-shapedchannel (160) in the tip (112) of a cannula system (100) similar to thatshown in FIG. 5A). For reference, FIG. 6A shows a schematic diagram ofsix treatment positions (arranged radially on a 4 mm diameter circlethus spaced a distance of about 2 mm from a center point (113)) in aplane 2 mm away from the target plane. FIG. 6B shows the relative dosedistribution for a system with a single fixed source (emanating source(401)) (e.g., Sr 90). The distance between the source midpoint and thetarget center is 2 mm away from the center of a target. For reference,FIG. 6D and FIG. 6E show a side view and a top cross sectional view,respectively, of a single source (a four-beaded Sr-90 source) againstdetectors at various distances from the source (e.g., 1.0 mm, 1.5 mm,2.0 mm, 2.5 mm, 3.0 mm, and 3.5 mm; the data used to compare with thesix-position source above is the 2.0 mm distance). FIG. 6F shows dosedistribution as surface plots and iso-dose lines (in Gy/min mCi) for thesource of FIG. 6D and FIG. 6E at the 2.0 mm distance from the sourcemidpoint.

In reference to figures from provisional application 61/877,765, FIG. 6Gand FIG. 6H show the 3D dose distribution of a generally annulus-likedistribution of emanating sources (401) (top) and a linear-shapedemanating source (401) (see configuration in FIG. 6D) (bottom) at 0.25mm from the source (FIG. 6G) and 2.0 mm from the source (FIG. 6H). Atthe 2 mm distance, the annulus-like distribution gives a more uniformdose across the diameter.

In reference to figures from provisional application 61/877,765, forcomparison, FIG. 6I shows the 3D dose distribution (top) and iso-doselines (middle) of a ring-shaped (annulus-like) emanating source (401)(bottom); FIG. 6J shows the 3D dose distribution (top) and iso-doselines (middle) of a horseshoe-shaped emanating source (401) (bottom).The horseshoe-shaped emanating source (401) approximates an annulus-likeshape.

The present invention is not limited to emanating sources (401)comprising Sr 90; other isotopes may be used (e.g., Y-90, Iodine-125,Cesium-131, Cesium-137, Ir-192, Ru-106, combinations of isotopes), andthe emanating sources (401) are not limited to any particular form ofradiation (e.g. emitters of alpha, beta, or gamma).

In some embodiments, an afterloading system (700) sends one or moreemanating sources (401) through the channels (160). For example, theafterloading system (700) may comprise multiple guide tubes (720), e.g.,one guide tube (720) for each channel (160) in the cannula system (100).

The tip (112) of the distal portion (110) of the cannula system (100)may be constructed in a variety of shapes and sizes. For example, insome embodiments, the tip (112) of the distal portion (110) of thecannula system (100) is rounded. In some embodiments, the tip (112) ofthe distal portion (110) of the cannula system (100) is an annulus or avariation thereof (e.g., partial annulus, a horseshoe shape, etc.). Forexample, FIG. 4A. FIG. 4B, FIG. 5, FIG. 6A, FIG. 6B, FIG. 6C and FIG. 7Ashow the tip (112) having a generally annulus shape. The tip (112) maybe any appropriate shape to accommodate the emanating source (401)and/or channels (160) and/or singular or multiple treatment positions(118).

In some embodiments, the emanating source (401) is directed through oneor more channels (160) to one or more treatment positions (118) that insummation deliver a dose to the target approximating that emanating froman annulus (or partial annulus).

Light Source Assembly

In some embodiments, the cannula system (100) comprises a light source.For example, in some embodiments, the cannula system (100) comprises alight source or in some embodiments, the cannula system (100) comprisesa means of emitting light from a distant source (e.g., a “light sourceemitter component (610)”, e.g., a fixture at the end of a fiber opticcable) connected, for example, via a fiber optic cable or light pipe(612). The light source (e.g., light source emitter component (610)) maybe positioned in any appropriate place on the cannula system (100). Forexample, in some embodiments, the light source (e.g., light sourceemitter component (610)) is positioned in the center of the distal end(112) of the distal portion (110) of the cannula system (100), e.g., asshown in FIG. 4A and FIG. 40. The light source (e.g., light sourceemitter component (610)) may be incorporated into the cannula system(100) or may be a separate system.

In some embodiments, the cannula system (100) comprises a light sourceassembly (600), wherein the light source emitter component (610) isincorporated into the light source assembly (600). For example, FIG.6A-60 show a fiber optic cable (612) with a light source plug (614)disposed on its end. The fiber optic cable (612) may be connected to anexternal light source.

In some embodiments, the light source emitter component (610) isincorporated into the light source plug (614). For example, in someembodiments, the light source emitter component (610) is disposed on thetip (616) of the light source plug (614). As shown in FIG. 6A, the lightsource plug (610) and light source emitter component (610)/tip (616) oflight source plug (614) are adapted to engage (e.g., slide into) a lightsource plug compartment (116) disposed in the tip (112) of the distalportion (110) of the cannula system (100). In some embodiments, thelight source plug compartment (116) is disposed in the center of the tip(112) of the distal portion (110) of the cannula system (100). In someembodiments, the light source plug compartment (116) is disposed in thecenter of the emanating sources (401) in the tip (112) of the cannulasystem (100) (see FIG. 6C). The placement and configuration of the lightsource plug compartment (116) is not limited to the positions andconfigurations shown herein.

In some embodiments, the tip (616) (e.g., light source emitter component(610)) of the light source plug (614) engages a light aperture (114)disposed on the bottom surface (e.g., the sclera-contacting surface) ofthe tip (112) of the cannula system (100). The light aperture (114) mayallow the tip (616) (e.g., light source emitter component (610)) of thelight source plug (614) to contact the sclera. This may allowtransmission of light through the sclera.

In some embodiments, the light source plug (614) is secured in the lightsource plug compartment (116) via a locking mechanism, e.g., a luer lockor other appropriate type of lock. In some embodiments, a groove (618)is disposed in the cannula system (100), e.g., in the distal portion(110) of the cannula system (100) adapted to engage the fiber opticcable (612) (see FIG. 6B).

As shown in FIG. 6C, the emanating source (401) may comprise one or morediscrete seeds, for example arranged in an annulus configuration (e.g.,equidistant from the center) or a continuous ring. The emanating source(401) configuration is not limited to the aforementioned configurations.For example, the discrete seeds may not necessarily be arrangedequidistant from the center, or the discrete seeds may not form anannulus configuration, or the continuous ring may be a partial ring orvariation thereof.

In some embodiments, a prism (613) is disposed at the end of the fiberoptic cable or light pipe (612). Without wishing to limit the presentinvention to any theory or mechanism, it is believed that the prism(613) may allow for transmission of light at a right angle from thefiber optic cable or light pipe (612) through the aperture (114).

Emanating Source Shapes and Radiation Emission Shapes

The present invention features emanating sources (401) and emanatingsource systems. An emanating source (401) may refer to an isotope/sourcethat emanates or emits radiation (see FIG. 12). An emanating source(401) may be a stand-alone radiation source, e.g., radioactive isotopeor radioactive isotope complexed with a carrier such as alloyed or aceramic carrier; or the emanating source (401) may comprise a jacket(402) (e.g., gold, titanium, stainless steel, platinum) or otherencasement (forming, for example, a “radionuclide brachytherapy source”(RBS), e.g., seed). In some embodiments, the emanating source (401)comprises a radiation shaper (406) to shape the emitted radiation fromthe emanating source (401). The emanating sources (401) or emanatingsource systems of the present invention may be used to treat wet AMD orany other appropriate disease or condition (e.g., lesion, tumor, etc.).

In some embodiments, the emanating source (401) is attached to a cannula(e.g., a cannula of the present invention or other cannula, e.g., a rod,tube, a solid stick, a hollow or partially hollow stick, a curvedcannula, etc.); for example, the cannula system (100) of the presentinvention may comprise an emanating source (401). In some embodiments,the emanating source (401) is a stand-alone unit (e.g., is not attachedto a cannula).

In some embodiments, the emanating source (401) has a radiation emissionshape (406) (e.g., shape of radiation emitted/shape of radiation at thetarget) of an annulus shape (or similar, e.g., a partial annulus), e.g.,the emanating source (401) is an “annulus emanating source” (401 a). Insome embodiments, the emanating source (401) (e.g., annulus emanatingsource (401 a)) is a stand-alone unit (e.g., is not attached to acannula).

In some embodiments, the emanating source (401) (e.g., annulus emanatingsource (401 a)) is attached to a cannula (e.g., a cannula of the presentinvention or other cannula, e.g., a rod, tube, a solid stick, a hollowor partially hollow stick, a curved cannula, etc.); for example, thecannula system (100) of the present invention may comprise an annulusemanating source (401 a). In some embodiments, the emanating source(401) (e.g., annulus emanating source (401 a)) is attached to the distalend of a cannula with a solid core, or a solid rod, or an applicatorthat is not a cannula. In some embodiments, the emanating source (401)(e.g., annulus emanating source (401 a)) is attached to the distal endof a solid rod of stainless steel. In some embodiments, the emanatingsource (401) (e.g., annulus emanating source (401 a)) is attached to thedistal end of a cannula with the Inner Diameter comprised of a lightpipe.

In some embodiments, the emanating source (401) (e.g., annulus emanatingsource (401 a)) is in the shape of an annulus (e.g., ring) (or similarshape, e.g., partial annulus, horseshoe shape, half-pipe shape, etc.),or a variation of an annulus (e.g., a square with a hollow center, arectangle with a hollow center, another geometric or symmetrical shape(rotationally symmetrical shapes) with a hollow center, etc.). In someembodiments, the emanating source (401) (e.g., annulus emanating source(401 a)) is not necessarily in the shape of an annulus, but the overallradiation flux/radiation emission shape (406) of the emanating source(401) is that of an annuls or similar shape. For example, in someembodiments, the emanating source (401) comprises one or multiple wiresthat together form a generally annulus-like radiation emission shape(406). Or, in some embodiments, multiple discrete emanating source (401)points have a cumulative annulus-like radiation emission shape (406).The emanating sources (401) are not limited to the configurationsdescribed herein.

Without wishing to limit the present invention to any theory ormechanism, it is believed that for beta radiation, or other radiation(e.g., gamma), the shape of an annulus may allow for a generally flatdosimetry across a broader diameter. Shapes approximating an annulus,e.g., a square made of four rectangular seeds, three, four, five, or six(or more) seeds evenly spaced around in a circle, a partial annulus(horseshoe), etc., may have similar dosimetry. Such dosimetry mayprovide improved dose homogeneity across a target (e.g., lesion, tumor),for example the dose may be substantially uniform across a target (e.g.,there is an absence of a dose hot spot center and the edges of thetarget may receive a more equivalent dose as at the center). In someembodiments, the annulus emanating source (401 a) (or similar shape) mayprovide a more uniform dose distribution throughout the depth of thetarget. In some embodiments, the shape of the emanating source is notnecessarily an annulus, but the resulting radiation flux at one of thesurfaces of the emanating source is in an annulus configuration (e.g., aring of discrete seeds, a source combined with a radiation shaper,etc.). In some embodiments, at one of its surfaces, the emanating sourcehas a resulting outwardly projecting radiation flux that comprises acentrally located attenuation zone and a surrounding peripheralradiation zone. The surrounding peripheral radiation zone may becontinuous or may be discrete regions (e.g., formed by discreteradiation units/seeds) of outwardly projecting radiation that surroundsthe attenuation zone. Further, as discussed above, an emanating source(401) may be an isotope/source itself that emanates or emits radiation(e.g., an annular shaped isotope seed). In some embodiments, anemanating source (401) may comprise a jacket (402) (e.g., gold,titanium, stainless steel, platinum) or other encasement which has anisotope embedded within, wherein the isotope seed itself does notprovide for an attenuation zone but the jacket is configured andconstructed to provide for the resulting attenuation zone at the surfaceof the emanating source at the surface of the emanating source (e.g.,the jacket comprising a centrally disposed radiation shaper). In someembodiments, the jacket and the seed embedded therein are configured andconstructed to provide for the resulting attenuation zone at the surfaceof the emanating source.

In reference to figures from provisional application 61/877,765, FIG.13A shows a comparison of dose rates in a target region for severalemanating source (401) designs. The ring (annulus) source has a morehomogenous dose distribution over the target zone as compared to thedisc source. FIG. 13B also shows a comparison of dose rates in a targetregion for several emanating source (401) designs: (a) 4 active seedsarranged side by side; (b) 4 seeds arranged side by side wherein onlythe outer 2 seeds are active; and (c) 4 active seeds arranged on thecircumference of a square. For the “4 active seeds on the circumferenceof a square, the maximum target dose rate per activity was nearly halfthat of the other two arrangements. And. the dose distribution over thetarget zone was more homogeneous for the “4 active seeds lying on thecircumference of a square” source as compared to the other twoarrangements.

In reference to figures from provisional application 61/877,765, FIG. 10shows an annulus-shaped emanating source. The dose to the target isgenerally uniform across the target's width. The annulus-shapedemanating source may be housed in a jacket (402), e.g., a disk-shapedjacket. FIG. 11A shows the annulus-shaped emanating source within ajacket (402) disposed at the tip (112) of the cannula system (100). FIG.11B shows the annulus-shaped emanating source disposed in the cannulasystem (100). The annulus-shaped emanating source is not limited to usewith a cannula system of the present invention. The annulus-shapedemanating source may be used alone or in combination with any otherappropriate cannula or device.

In some embodiments, a radiation shaper (404) is used to shape theradiation emitted from the emanating source (401). In some embodiments,the emanating source (401) is not annulus shaped, but the radiationshaper (404) creates an annulus-shaped radiation emission shape (406).Thus, while the emanating source (401) is not annulus-shaped, the effectof the radiation shaper (404) is still an annulus-shaped emanatingsource (401). FIG. 12 shows a disk-shaped emanating source (401 b)) anda rounded radiation shaper (404). The radiation shaper (404) blocks theradiation (or a portion thereof) in its path (e.g., limiting theradiation traveling to the target).

As previously discussed, in some embodiments, the emanating source (401)may be in the shape of an annulus or similar. In some embodiments, theemanating source (401) is constructed in any other shape but is pairedwith a radiation shaper (404) that shapes the radiation that reaches thetarget (the radiation emission shape (406)) in the shape of an annulusor similar (or the summation of the discrete points of radiation iseffectively similar to an annulus or similar shape). The emanatingsources (401) and emanating source systems are not limited to theaforementioned configurations. For example, in some embodiments, theemanating source (401) is in the shape of a rotationally symmetricalshape (see FIG. 9A).

In some embodiments, the emanating source (401) is complexed with acarrier. In some embodiments, the emanating source (401) is complexedwith a radiation shaper, and the emanating source (401) and radiationshaper are together housed in a jacket or encasement (e.g., stainlesssteel, gold, or titanium). In some embodiments, the emanating source(401) is housed in a jacket or encasement and a radiation shaper isdisposed external to the jacket (402) or encasement. In someembodiments, “active material” refers to the emanating source. In someembodiments, “active material” refers to the emanating source complexedwith a carrier.

In some embodiments, the emanating source (401) comprises an attenuationzone (410) that has either reduced or eliminated radiation emitted fromthe region. For example, in some embodiments, the emanating source (401)comprises an attenuation zone (410), wherein the attenuation zone (410)is a hole. The hole (414) may create an annulus-shaped emanating source(401). In some embodiments, the attenuation zone (410) is an indentation(416). In some embodiments, the attenuation zone (410) comprises ashield for shielding or partially shielding radiation emitted from theattenuation zone (410). Again, the attenuation zone (410) may beachieved by combining a radiation shaper (404) in combination with theemanating source (401), thereby shaping the radiation emission shape(406). Non-limiting examples of such emanating sources (401) are shownin FIG. 10. The emanating sources (401) are not limited to the shapesand configurations shown herein.

FIG. 9B (and FIG. 9A) shows examples of possible shapes of the emanatingsources (401) or the radiation emission shape (406). The attenuationzone (410) is not limited to a circular shape (or a square shape,triangular shape, oval shape, etc.).

The attenuation zone (410) may allow the emanating source (401) toachieve a substantially flat dose rate both at the central area of thetarget as well as across the diameter of the target (as compared to adisk-shaped emanating source/radiation emission shape).

In some embodiments, the dose that is emitted from the attenuation zone(410) is about 10% less than the dose emitted from the outer edge (412)of the attenuation zone (410). In some embodiments, the dose that isemitted from the attenuation zone (410) is about 15% less than the doseemitted from the outer edge (412) of the attenuation zone (410). In someembodiments, the dose that is emitted from the attenuation zone (410) isabout 20% less than the dose emitted from the outer edge (412) of theattenuation zone (410), In some embodiments, the dose that is emittedfrom the attenuation zone (410) is about 25% less than the dose emittedfrom the outer edge (412) of the attenuation zone (410). In someembodiments, the dose that is emitted from the attenuation zone (410) isabout 30% less than the dose emitted from the outer edge (412) of theattenuation zone (410). In some embodiments, the dose that is emittedfrom the attenuation zone (410) is about 40% less than the dose emittedfrom the outer edge (412) of the attenuation zone (410). In someembodiments, the dose that is emitted from the attenuation zone (410) isabout 50% less than the dose emitted from the outer edge (412) of theattenuation zone (410). In some embodiments, the dose that is emittedfrom the attenuation zone (410) is about 60% less than the dose emittedfrom the outer edge (412) of the attenuation zone (410). In someembodiments, the dose that is emitted from the attenuation zone (410) isabout 70% less than the dose emitted from the outer edge (412) of theattenuation zone (410). In some embodiments, the dose that is emittedfrom the attenuation zone (410) is about 80% less than the dose emittedfrom the outer edge (412) of the attenuation zone (410). In someembodiments, the dose that is emitted from the attenuation zone (410) isabout 90% less than the dose emitted from the outer edge (412) of theattenuation zone (410). In some embodiments, the dose that is emittedfrom the attenuation zone (410) is about 100% less than the dose emittedfrom the outer edge (412) of the attenuation zone (410).

As previously discussed, the emanating source (401) is not limited tothe configurations described herein. For example, in some embodiments,the emanating source (401) comprises one or multiple wires that togetherform a generally annulus-like radiation emission shape (406). Or, insome embodiments, multiple discrete emanating source (401) points have acumulative annulus-like radiation emission pattern (radiation emissionshape).

In some embodiments, the attenuation zone (410) is proportional in sizeto the remaining area of the emanating source (401) shape (or radiationemission shape (406)) such that the dosimetric profile delivers asubstantially flat dose rate over the entire area contained by theemanating source (401) (including over the attenuation zone (410), whichmay have reduced or absent radiation emission as compared to theremaining area of the emanating source (401)/radiation emission shape(406)).

In reference to figures from provisional application 61/877,765, FIG.13A shows modeled emanating sources (401), e.g., a disc and rings withan outer diameter of 4 mm and a thickness of 0.1 mm. The rings had innerdiameters of 2.0, 3.0, 3.5 and 3.6 mm. As the inner diameters increased(holes were bigger), there was more homogeneity of dose distribution.The emanating source (401) may be customized according to lesion sizeand depth. For example, the emanating source (401) may comprise a ringwith an inner diameter greater than 3.6 mm or less than 2.0 mm, theemanating source (401) may have a larger or smaller thickness than 0.1mm, the emanating source (401) may have a larger or smaller outerdiameter than 4 mm, etc. FIG. 17 shows a disc-shaped emanating source(401) (left) and a ring-shaped emanating source (401) (right), e.g., anannulus-shaped emanating source (401). These configurations were used tocalculate the dosimetry shown in FIG. 13A.

FIG. 8 shows radiation flux (450) for two annulus emanating sources: (a)an annulus-shaped emanating source and a disc-shaped emanating sourcepaired with a radiation shaper. The resulting radiation emission shape(406) is that of an annulus configuration.

As used herein, the term “about” refers to plus or minus 10% of thereferenced number.

Various modifications of the invention, in addition to those describedherein, will be apparent to those skilled in the art from the foregoingdescription. Such modifications are also intended to fall within thescope of the appended claims. Each reference cited in the presentapplication is incorporated herein by reference in its entirety.

Although there has been shown and described the preferred embodiment ofthe present invention, it will be readily apparent to those skilled inthe art that modifications may be made thereto which do not exceed thescope of the appended claims. Therefore, the scope of the invention isonly to be limited by the following claims. Reference numbers recited inthe claims are exemplary and for ease of review by the patent officeonly, and are not limiting in any way. In some embodiments, the figurespresented in this patent application are drawn to scale, including theangles, ratios of dimensions, etc. In some embodiments, the figures arerepresentative only and the claims are not limited by the dimensions ofthe figures. In some embodiments, descriptions of the inventionsdescribed herein using the phrase “comprising” includes embodiments thatcould be described as “consisting of”, and as such the writtendescription requirement for claiming one or more embodiments of thepresent invention using the phrase “consisting of” is met.

The reference numbers recited in the below claims are solely for ease ofexamination of this patent application, and are exemplary, and are notintended in any way to limit the scope of the claims to the particularfeatures having the corresponding reference numbers in the drawings.

What is claimed:
 1. A brachytherapy system comprising a cannula system(100) for insertion into a potential space between a sclera and aTenon's capsule of an eye of a patient, the cannula system (100)comprises a distal portion (110) with a tip (112), a channel (160)extends through the cannula system (100) to the tip (112), the channel(160) comprises at least one treatment position (118) in the tip (112)for an emanating source (401).
 2. The system of claim 1, wherein theemanating source (401) is directed through one or more channels (160) toone or more treatment positions (118) that in summation deliver a doseto the target approximating that emanating from an annulus.
 3. Thesystem of claim 1, wherein the tip (112) of the cannula system (100) isdisk-shaped.
 4. The system of claim 1, wherein the emanating source(401) is an annulus or a partial annulus.
 5. The system of claim 1,wherein the emanating source (401) is linear.
 6. The system of claim 1,wherein the emanating source (401) comprises one or more discrete seeds.7. The system of claim 6, wherein the discrete seeds are arranged in anannulus or partial annulus configuration.
 8. The system of claim 1,wherein the emanating source (401) comprises a continuous ring or aportion of a ring.
 9. The system of claim 1 further comprising a lightsource assembly (600).
 10. The system of claim 9, wherein the lightsource assembly (600) comprises a fiber optic cable or light pipe (612)operatively connected to an external light source, a light source plug(614) is disposed on an end of the fiber optic cable or light pipe(612), a light source emitter component (610) is incorporated into thelight source plug (614), the light source plug (610) and light sourceemitter component (610) are adapted to engage a light source plugcompartment (116) disposed in the tip (112) of the distal portion (110)of the cannula system (100), wherein the light source plug (614) andlight source emitter component (610) engage a light aperture (114)disposed on a bottom surface of the tip (112) of the cannula system(100).
 11. The system of claim 10, wherein a prism is disposed at theend of the fiber optic cable or light pipe (612).
 12. The system ofclaim 10, wherein the light source plug (614) is secured in the lightsource plug compartment (116) via a locking mechanism.
 13. The system ofclaim 10, wherein a groove (618) is disposed in the cannula system (100)adapted to engage the fiber optic cable or light pipe (612).
 14. Thesystem of claim 1 further comprising an afterloading system (700) fordelivering the emanating sources (401) (400) to the treatmentposition(s) (118).
 15. The system of claim 14, wherein the afterloadingsystem (700) comprises a guide tube (720) for each channel (160) in thecannula system (100).
 16. The system of claim 14, wherein theafterloading system (700) comprises: a vault (710) for storage of anemanating source (401), wherein the emanating source (401) is attachedto an advancing means (722); a guide tube (720) extending from the vault(710), the guide tube (720) is removably attachable to the cannulasystem (100); and a source-drive mechanism (730) operatively connectedto the advancing means (722), wherein the source-drive mechanism (730)advances the emanating source (401) through the guide tube (720) to thetreatment position (118) in the cannula system (100).
 17. The system ofclaim 1, wherein the emanating source (401) provides a dose rate ofbetween about 1 to 10 Gy/min to a target.
 18. The system of claim 1,wherein the cannula system (100) comprises a proximal portion (120)connected to the distal portion (110) by an inflection point (130), thedistal portion (110) has a radius of curvature between about 9 to 15 mmand an arc length between about 25 to 35 mm and the proximal portion(120) has a radius of curvature between about an inner cross-sectionalradius of the cannula system (100) and about 1 meter.